Re: [Qemu-devel] [PATCH] block: Always call bdrv_child_check_perm first

[Fam Zheng <famz@redhat.com>]

On Wed, 03/15 11:52, Kevin Wolf wrote:
> Am 14.03.2017 um 03:30 hat Fam Zheng geschrieben:
> > bdrv_child_set_perm alone is not very usable because the caller must
> > call bdrv_child_check_perm first.
> 
> Well, you can imagine use cases where you want to check multiple
> children first and then set or abort all of them, but apparently we
> haven't found such a case yet, so I'm fine with making the functions
> private for now.  If we ever need it, making them public again is
> trivial.

Yes, no problem with that use case but by then I suppose we should also add an
assertion about the calling sequence: e.g. in image locking, raw_set_perm goes
nut if not preceded by `raw_check_perm.

> 
> > This is already encapsulated
> > conveniently in bdrv_child_try_set_perm, so remove the other prototypes
> > from the header and fix the one wrong caller, block/mirror.c.
> > 
> > Signed-off-by: Fam Zheng <famz@redhat.com>
> 
> Thanks, applied to the block branch.

Thanks!

Fam

> 
> Kevin